The amino acids in collagen set it apart from any other protein. Collagen has an amino acid profile that’s totally unique, even among other animal proteins. This unique profile makes collagen especially good at building and repairing tissue, which is great news for athletes.
What’s collagen’s secret? Three little amino acids – tiny molecules that make up every protein in every cell for every living thing on Earth. Understanding what amino acids are in collagen and why that makes a difference in your fitness goals can help you make better protein choices.
An overview of amino acids can help guide your dietary decisions as you work through your goals.
But before we ever talk about amino acids, let’s introduce the star of the show: collagen.
What is collagen?
Collagen is the most abundant protein in the human body. You have collagen in your bones, muscles, veins, arteries, organs, joints, skin, hair, and nails. Collagen is a versatile protein because it’s strong enough to provide structural support but stretchy enough to bend and twist without breaking.
Your body produces its own collagen throughout your life, but production slows as you age. If you’re deficient in any of the amino acids in collagen, you may have slower collagen production than you otherwise would.
Collagen can also be found in the foods we eat. This is called “dietary collagen”. Dietary collagen can be found in animal products like meat, fish, eggs, and dairy. There’s no true source of vegan collagen, and “vegan collagen” supplements are really full of nutrients to help boost your body’s natural collagen production.
Anyone familiar with dietary proteins like dietary collagen is familiar with the idea of complete vs incomplete proteins. So which one is collagen?
Technically, collagen is an incomplete protein, which means it only contains 8 of the 9 essential amino acids. We’ll talk more about collagen as an incomplete protein later on when we review what amino acids are in collagen.
What are amino acids?
Before we go any further, let’s introduce our “co-star”: amino acids. What are amino acids? They’re molecules that can link up to form peptides – short chains – or proteins.
A protein is a complex chain of 20 or more amino acids. Proteins provide structural support and run nearly every function in your cells. And they couldn’t do it without amino acids!
There are more than 500 amino acids on Earth, but the human body only uses 20 of them that we know of. These 20 amino acids can be separated into two broad categories: essential and non-essential.
Essential amino acids must be consumed in your diet. Your body needs them to function, but can’t make them.
There are 9 essential amino acids in total: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. There are 8 essential amino acids in collagen, and we’ll talk about each of them today, as well as the functions they perform in your body.
Non-essential amino acids are ones your body can make, but there’s a catch. About half of the non-essential amino acids are “conditionally” essential. This means that in certain circumstances, like illness, injury, or pregnancy, your body can’t keep up with the demand for them.
This makes consuming both essential and non-essential amino acids important for your overall health.
There are 11 non-essential amino acids: alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine. You can find all 11 of the non-essential amino acids in collagen.
What amino acids are in collagen?
Let’s revisit the question from earlier again: is collagen a complete protein? No, because a complete protein has all 9 essential amino acids. Collagen has 8 of the 9 but is missing one: tryptophan. This keeps it from being a complete protein, but doesn’t prevent it from being a powerful one!
Collagen still has all 11 non-essential amino acids, including a particularly powerful triple-helix of amino acids. So what amino acids are in collagen?
Essential amino acids in collagen
Collagen contains nearly all of the essential amino acids, but what do these amino acids do in your body?
Histidine is one of the most versatile essential amino acids and is used in the creation of different proteins – red and white blood cells in particular. Your body also uses histidine to make histamine, a crucial part of your immune response.
Isoleucine, another of the amino acids in collagen, is used for wound healing and helps regulate blood sugar and energy levels.
Leucine is related to isoleucine, so it functions very similarly and is also related to the production of human growth hormone.
Lysine helps your body absorb calcium and form collagen and plays a role in hormone regulation.
Methionine absorbs micronutrients like zinc and helps your body detoxify itself from heavy metals like lead and mercury.
Phenylalanine helps your body access other amino acids and enzymes, so it acts as a precursor to other hormonal changes in your body. Phenylalanine is often found in aspartame, so people who consume artificial sweeteners may already be getting a high dose of this amino acid.
Threonine helps your body form collagen and is a strong component of healthy tooth enamel.
The last of the amino acids in collagen, valine, promotes tissue repair and muscle growth and may help regulate energy.
You might notice a pattern – most of the essential amino acids help your body form proteins or build and repair muscle tissue. That’s why getting plenty of essential amino acids is so important! But what do the non-essential amino acids do?
Non-essential amino acids in collagen
You’ll get all 11 non-essential amino acids in collagen, so let’s take a look at what these do in your body. All non-essential amino acids can be used in protein formation, so we’ll focus on the other benefits they have to offer.
Alanine helps your body break down tryptophan and vitamin B6 and provides energy for your muscles.
Arginine is a key player in cell communication, blood flow, and immune response.
Asparagine also helps with cell communication in your neurons, as well as removing toxins like ammonia from your cells.
Aspartic acid also helps with neuron communication and energy production.
Another of the non-essential amino acids in collagen, cysteine, is central to collagen’s elasticity and helps your body make collagen. Cysteine also acts as an antioxidant.
Glutamic acid is involved in learning and memory. It’s one of the most important amino acids in neuron communication and can also act as an energy source for neurons.
Glutamine is a natural detoxifier, helping to remove ammonia from your cells. Glutamine also helps your immune system function normally and may play a role in healthy digestion.
Glycine, one of the most important amino acids in collagen, acts as an antioxidant and can be a quick energy source for your cells. Glycine is also one of the most common amino acids in a collagen protein, but we’ll talk more about that in a moment.
Proline also plays a role in antioxidant responses and helps run your body’s immune system and ability to heal wounds.
Serine works to strengthen neurotransmitters and helps your body to create other non-essential amino acids.
And finally, tyrosine, which helps produce melanin and regulate hormones.
Of all these amino acids, three are especially important in collagen. These three amino acids give collagen amazing healing and strengthening powers, but what are they?
The most important amino acids in collagen
Collagen protein has a triple helix structure made of three amino acids: glycine, proline, and hydroxyproline.
Now, hydroxyproline isn’t on either of the lists above, because it’s a little different from the other two amino acids. Hydroxyproline is an amino acid the body creates by adding hydrogen and oxygen to proline. This happens almost exclusively when the body creates or breaks down collagen.
Combined, these amino acids make up about 50% of all the amino acids in collagen. Glycine accounts for the most, at about 30% of all amino acids in collagen. Glycine holds the triple helix structure in collagen together. And that triple helix, in turn, helps to hold your body together!
Getting glycine in your diet is essential because this means that if your body doesn’t have enough glycine, it can’t make collagen.
What about tryptophan?
Tryptophan is an essential amino acid, and it’s the only one collagen that is missing. Most people have heard of tryptophan in the context of Thanksgiving turkey since turkey has naturally high levels of tryptophan.
Tryptophan helps your body create serotonin, which means it plays a key role in your sleep schedule and mood. Since it’s an essential amino acid and it’s not one of the amino acids in collagen, you’ll need to make sure you consume other foods with tryptophan to stay healthy.
Choosing a collagen supplement fortified with tryptophan is a great way to make sure you don’t miss out on this essential nutrient! Supplementing with tryptophan alone is another option, but finding cost-effective, high-quality amino acid supplements can be tricky.
Amino acids and collagen supplements
Amino acids and collagen are both found in foods we eat, but they’re also available to purchase as supplements. When purchasing any supplement, you want to look for medical-grade supplements, since these are held to the highest quality control standards by the FDA. Stocking up on multiple supplements can get expensive quickly, though, so which one is better?
Amino acids aren’t too different in a supplement compared to how they appear in the foods you eat. They’re already such small molecules that there isn’t too much to change when they’re put into a supplement. Collagen benefits, however, are different depending on how you consume it.
Supplements can change the amino acids in collagen and how your body processes it, so what should you look for in a supplement?
Fortified collagen supplements
Some collagen supplements are fortified to contain tryptophan. This means that your collagen supplement is now a complete protein. These supplements put all the amino acids in collagen, so you don’t have to worry about including tryptophan elsewhere in your diet.
Not all collagen supplements are fortified, so it’s important to check labels. While you’re reading those labels, there are a few things to keep an eye out for. Make sure your supplement doesn’t have any fillers like sugar, wheat, soy, cornstarch, and artificial colors or flavorings.
Hydrolyzed collagen supplements
Once you know you have all the amino acids in a collagen supplement, make sure it’s also hydrolyzed. You may see hydrolyzed collagen labeled as “collagen peptides” instead, but these are two names for the same product.
Hydrolyzed collagen is collagen that has been broken down into smaller chains of amino acids. These are the collagen peptides, and they’re much easier for your body to digest. In its natural state, collagen is a very large protein, and your body can have a difficult time digesting it.
This means that much of the collagen you consume can pass through your system undigested, so you don’t get the benefits of the amino acids in collagen. Hydrolyzed collagen prevents this, because the peptides are much easier to digest!
Using collagen and amino acids for fitness
The amino acids in collagen are all central to your body’s overall health and wellness. Understanding what amino acids are in collagen and why each of them is important can help you make the best dietary choices.
Supplementing with hydrolyzed collagen protein that has been fortified with tryptophan is one of those choices. In just a few moments every day, you’ve given your body all the essential and non-essential amino acids it needs to keep you healthy from head to toe.